Sight glass



FIG. 1 is a perspective view of the sight glass of my new design;

FIG. 2 is a front elevational view thereof, the rear elevational view is a mirror image thereof;

FIG. 3 is a side elevational view of the left side thereof;

FIG. 4 is a side elevational view of the right side thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is a perspective view of a first modification of the sight glass of my new design;

FIG. 8 is a front elevational view of FIG. 7, the rear elevational view is a mirror image thereof;

FIG. 9 is a side elevational view of the left side of FIG. 7;

FIG. 10 is a side elevational view of the right side of FIG. 7;

FIG. 11 is a top plan view of FIG. 7; and,

FIG. 12 is a bottom plan view of FIG. 7. 

The ornamental design for sight glass, as shown and described. 